Fire hydrants are an essential part of any modern fire fighting system and are thus very common in urban and suburban areas in many countries around the world. Their high density in numbers and their locations, usually in open public places, raise a number of problems. As fire hydrants provide direct access to a city's water main, fire hydrants can easily be used to steal large amounts of water from a municipal authority or a utility provider. Moreover, due to the fact that tampering with standard fire hydrants may take a long time to detect, a significant loss of water can also be caused by vandalism or mischief. In the course of tampering, the fire hydrant can be damaged, creating situations where fire-fighting personnel are unable to operate the fire hydrant in an emergency situation. Additionally, fire hydrants can be used to contaminate at least a part of a municipal water system by injecting contaminants through the fire hydrant into the city's water main.
Systems for the prevention of tampering with fire hydrants as well as for monitoring fire hydrants are known in the art. U.S. Pat. No. 7,980,317 issued to Preta et al. entitled “Smart monitor for fire hydrants” is directed to a system for monitoring fire hydrants which detects and notifies a utility provider when the fire hydrant is being activated or when it should be serviced. The system comprises a monitor module which includes a module-nut, an alert element and various electronic components. The monitor module is associated with the operating nut of the fire hydrant through an operating nut receiver secured to the operating nut with one or more securing pens. The module-nut protrudes from the top surface of the monitor module and is mechanically associated with the fire hydrant's operating nut so that the module-nut is used for turning the fire hydrant on and off. The alert element is configured to provide a visual signal in three different directions. The electronic components of the monitor module include a processing device, a memory, a camera, an audio module, an RF transceiver, various sensors, a GPS system and an electronic lock. The memory is used for storing image and sound data as well as data from the various sensors. The camera and audio module are configured to record images and sounds when the fire hydrant is activated. The RF transceiver is used for transmitting information to a utility provider including activation data as well as data relating to the maintenance of the fire hydrant. The activation data may include the time of activation or the amount of water consumption, while maintenance-related data may include a notification that the fire hydrant should be serviced. The transceiver is also used to allow remote access to the monitor module such as activating the alert element remotely by the utility provider. The sensors are used for detecting an activation of the fire hydrant and monitoring various parameters relating to the operation of the fire hydrant, such as counting the number of turns of the operating nut, checking the lubricating chamber of the fire hydrant for sufficient lubricant, monitoring the temperature of the fire hydrant or detecting back flow from the fire hydrant. The electronic lock may be a software lock for preventing access to various functions of the monitor module, or a mechanical lock that prevents the fire hydrant's output ports from being opened.
U.S. Patent Application Publication No. 2004/0129312 to Cuzzo et al. entitled “Water system tampering sensing device” is directed to a water system protection device, and in particular to a device for protecting fire hydrants against tampering. The system includes two portions with hasps connected at their ends by a hinge. The system further includes a locking device, an anti-tempering device, sensors, a transmitter, a receiver and an interface access port. The two portions are closed over the upper part of the fire hydrant forming a donut shape preventing access to the fire hydrant's nozzles. The two portions are locked together using the locking device connecting together the hasps. The locking device may be a key or combination lock, a ring, a wire or the like. The anti-tempering device may be a break detection wire embedded in the two portions, such that opening the two portions causes the break detection wire to split, providing an indication that the fire hydrant has been tampered with. Further indication of tampering is given by the sensors such as vibration sensors, tilt switches, pressure switches, and temperature switches. When the break detection wire or the sensors provide an indication of tampering, the transmitter sends an encrypted signal to a central monitoring facility identifying the location of the fire hydrant. The interface access port enables authorized personal to access the fire hydrant by entering a deactivation code. The interface access port may have a wireless interface where the authorized person uses a wireless device in order to gain access. The water system protection device may also allow access to the fire hydrant via the receiver which can receive a temporary deactivation code from the central monitoring facility.
The “KingLock Hydrant Lock,” a product of the company www.kinglock.us (and disclosed on the website http://www.pollardwater.com/pagesproduct/kingLock.asp or on the web site http://www.kinglock.us), is directed to a device for preventing access to the operating nut of a fire hydrant and for sounding an alarm when the device is breached. The device includes an operating nut extender, an outer shell comprised of a base part and a hinged cover, a stainless steel locking pin, two hex wrenches that are used as retainer pins and an alarm package. The device may further include a transceiver and sensors. The operating nut extender is secured to the fire hydrant's operating nut. The outer shell is placed over the operating nut extender and secured in its place by the locking pin which is inserted horizontally though a hole in the side wall of the outer shell into a groove in the operating nut extender. This configuration allows the outer shell to rotate freely around the operating nut extender. The locking pin in its turn is locked in its place by the two hex wrenches that are inserted vertically through two holes in the top surface of the base part of the outer shell. The alarm package together with the transceiver and sensors may be installed inside the inner cavity of the hinged cover. The base part and the hinged cover of the outer shell include hasps that allow the hinged cover to be locked in a closed state using a standard lock. Once the device is installed the fire hydrant can be turned on and off through the operating nut extender when the hinged cover is open. When the hinged cover is closed there is no access to the operating nut extender or to the hex wrenches which secure the locking pin. The alarm package includes a keypad for entering an alarm code. Once the hinged cover is opened the alarm package will sound an alarm after a predetermined time unless the alarm code is entered. The transceiver may be used for mesh network communications.